AGGRCOW  Aggressive cows
Farmer John has built a new long barn, with N (2 <= N <= 100,000)
stalls. The stalls are located along a straight line at positions
x1,...,xN (0 <= xi <= 1,000,000,000).
His C (2 <= C <= N) cows don't like this barn layout and become
aggressive towards each other once put into a stall. To prevent the
cows from hurting each other, FJ wants to assign the cows to the
stalls, such that the minimum distance between any two of them is
as large as possible. What is the largest minimum distance?
Input
t – the number of test cases, then t test cases follows.
* Line 1: Two spaceseparated integers: N and C
* Lines 2..N+1: Line i+1 contains an integer stall location, xi
Output
For each test case output one integer: the largest minimum distance.
Example
Input:
1 5 3 1 2 8 4 9
Output:
3
Output details:
FJ can put his 3 cows in the stalls at positions 1, 4 and 8,
resulting in
a minimum distance of 3.
hide comments
arun m dabbe:
20200215 08:43:29
Very interesting problem , classic . 

sayan_244:
20200130 15:46:11
>.> You need to be bit lucky for the greedy approach to strike. Took me a whole day.


abhi1999:
20200123 15:20:28
Where can i find solution of the problem


transonviet:
20200102 05:32:50
AC in one go


heromayank2:
20191224 15:20:19
Poor Explanation 

hellb0y_suru:
20191217 20:39:46
AC in one go !!!


saurav_03:
20191208 10:10:49
interesting problem


saurav_23:
20191026 08:52:01
AC in one go! Good question but sample test case could've been better. 

gadela_kesav4:
20191017 18:34:03
Test cases are not up to mark showing correct answer even if coded wrong


dhairya_2000:
20190929 13:22:29
Finally One Correct in One Go!! 
Added by:  Roman Sol 
Date:  20050216 
Time limit:  2s 
Source limit:  10000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  USACO February 2005 Gold Division 